FateReckoning
by Lord Winterman
Summary: Following the Fourth Holy Grail War, Kiritsugu Emiya makes one final effort to fulfill a promise he made, no matter what it might cost him. A one-shot that will eventually be expanded into a larger story.


**A/N: Though a bit late for Father's Day, I decided to drum this little bit out. As this came from a larger concept I've been working on, expect some gaps in the story. Also, there are spoilers, primarily involving the events of Fate/Zero.**

Kiritsugu breathed deeply, then exhaled slowly, his breath visible in the frigid air. The weather was just barely acceptable for this operation, but it would be enough to conceal their approach. Across from him, Gallagher Fraga McRemitz tugged his rune-enhanced gloves over his hands.

"This is not what I had in mind when you requested my services," the Irishman said.

"Then let's hope our friends are enough of a distraction," Kiritsugu replied, then looked at his watch. "Thirty seconds."

The pilot nodded, and Gallagher said nothing as he met the Mage Killer's eyes, the last seconds ticking down.

It had taken a considerable amount of resources to put this together, and he wasn't entirely sure if they could pull it off. Still, he had cash to burn, and more than a few contacts gathered over the years to make it plausible.

A ripple of explosion shook the ground, disturbing the ley lines and the Bounded Field powered by them, revealing the Einzbern Castle once more to his eyes.

For anything else, this amount of explosives would have been overkill. For three people laying siege to a mage's castle, Kiritsugu was concerned it wouldn't be enough. As it stood, the Bounded Field would be up again in a matter of minutes.

Before the Fourth Holy Grail War, he would have been able to disrupt the Bounded Field by himself, rending the need for assistance entirely moot. He had been a part of the family then.

By Old Man Acht's reckoning, Kiritsugu had betrayed the Einzberns. He had not been allowed to explain anything, and had been barred from the castle, forbidden to see his daughter. For failing to bring them the Grail, that last one was to be the ultimate punishment.

But even with his magical and physical strength waning, Kiristugu had earned the moniker "Mage Killer" for a reason, and amidst his many broken promises, he planned to keep one that mattered the most.

"Go!"

The two jumped out from the helicopter, parachutes deploying and slowing them to a safe descent onto the roof, then immediately went to breach the windows below. Another helicopter swooped down and dropped a team of mercenaries hired by the Musik family began sweeping the lower floors.

One handy resource he had gathered during his career was finding who had grudges with whom, especially within the Association. The Musik family's interest in the Einzberns' homunculus secrets was an easy sell, and their enthusiastic investment in the operation was almost pathetic.

Kiritsugu had no illusions about the nature of their alliance, and had taken the appropriate measures to safeguard his personal mission's success, his own transport and help being only the most visible of his contingencies. Likewise, he was sure Acht wouldn't let the intruders abscond with anything actually important, and would likely repel the incursion in short order, meaning he and his partner needed to move fast.

As he made to breach, he fired a burst from his AUG, flying through shattered glass. Fortunately, there was no one guarding the room, though he expected the attendants would respond shortly.

And then he spotted his daughter looking around, bleary-eyed at the sudden commotion within and around the castle, but she was wide awake when she saw who had just burst into her room.

"Daddy?" she asked, disbelieving her eyes.

Slinging his rifle over his shoulder, Kiritsugu ran over to his daughter, pulling her into a hug.

"I'm here, Illya, just like I promised," he said, stroking her hair. "But we need to leave."

The door slammed open as one of the guards stormed in. Gallagher chucked a rune-inscribed stone, detonating like a flashbang grenade, allowing him to close distance and subdue the homunculus.

"We need to move," Gallagher said.

"Alright, Illya, you need to go with Gallagher. I will be close behind you."

Surprisingly, Illya was undisturbed by the violence taking place, and did not protest as Kiritsugu threw his coat around her and handed her to Gallagher.

Making sure the room remained clear as they exited, he leaned out into the hall, spraying a hail of gunfire down the hall, shredding the other homunculus approaching them down before they could properly react to his presence, then ran back to the window for the final descent to the ground, leaving a farewell present.

By the time Gallagher and Illya were on the ground, Kiritsugu not far behind, their ground transport pulled up, a Humvee he had acquired and modified for this exact purpose. Gallagher deposited Illya in the back and clambered in, the Mage Killer took shotgun.

"Punch it!" he ordered, even before the doors were closed.

The driver quickly responded, and snow spewed out behind them as they peeled towards their exfiltration point. An explosion thundered at the castle, the present casting chunks of masonry and his family's old suite.

Behind him, he could see the Musik group doing the same, at a different vector and pursued by homunculus, maintaining their attack even as the intruders sped out of range and view.

 _That's one objective cleared,_ Kiritsugu thought.

[F/R]

Kiritsugu Emiya was counting on every shred of training he had acquired over his career to keep himself awake for the final stretch of his journey. His lone passenger was sleeping peacefully in the back seat. He could hardly fault her on that, but on the other hand, she would have loved to see an actual, living city instead of the cold white of the Einzbern Castle.

 _There will be time for that later,_ he thought to himself.

After the ordeal they had both been through, he decided it was time for an actual vacation, but that could wait until they had all recovered.

He pulled to a stop in the driveway. His passenger stirred when at the cessation of movement, and the vehicle powering down. Thankfully, she did not protest him unfastening her and scooping her up in his arms to carry her inside. As light as she was, he still found his strength beginning to fade.

But it was enough.

He opened the gate and strode across the grounds to the house. Lights were still on and he could hear the TV was on. The bundle in his arms began to squirm, so he set her down, but she still held his hand tightly.

"Shirou, I'm back."

There was the sound of scuffling in the living room, followed by running towards the entry way, then a boy with reddish hair slid into view. He was about to run up for a hug when he saw the girl clinging to Kiritsugu's leg.

"Illya, this is your brother."

The boy stared blankly at the white-haired girl with red eyes, who then broke into a bright smile.

"It's nice to meet you," she said. "I hope we can be friends!"

 _Welcome home, Illya._

 **A/N: While I know most of the reasons – in-universe and out – for why this scenario never happened, I still wondered what how things would have gone down if Kiritsugu had been able to act like the Mage Killer for one final time.**

 **If high explosives can constitute a solution to the Grail (to my understanding, this is what Kiritsugu had planned in canon, but events proceeded quicker than expected), why not use them for rescuing your daughter from your demented in-laws? Plenty of people would sell their souls for that opportunity, and for weaker justification. He was a long-time hired assassin and mercenary with few personal expenditures outside of the basic necessities, he probably had quite a stash of cash and other resources to call upon to throw at the problem.**

 **Like Reunion, this little bit will eventually be expanded into a larger story in the future, but for now, it will remain a one-shot as I continue to do research to hammer it out properly. Any additional story details can wait until then, but anyone with an understanding of the world of Fate/Stay Night and the various spin-offs and what-not can probably make some educated guesses as to what may be included in the larger project.**

 **As always, constructive criticism is appreciated. As most of my knowledge comes from the various anime series and what I've found on the wiki, I'm probably going to be a little off on some things, and not all of them deliberate.**

 **Anywho, I'll cut this note before it gets any longer.**


End file.
